how to turn off vibrate for alarm on iphone 5 ios 6?

with the release of the iphone 5, apple changed the dock connection...so i can no longer use it with my ihome alarm clock without an adapter.

since apple has not yet made available the adapter, i've been using alarm in the clock app to wake-up.

i love that i can set the alarm to a song...but i do not like that it vibrates when the alarm goes.

how do i turn off the vibration for the alarm on my iphone 5 running ios 6?

thanks.